1. Field of the Invention
This invention relates to further improvements in pipette samplers and related systems.
2. Prior Art
The use of various sized and shaped pipettes for withdrawing liquid samples from a container so as to measure the same and transfer it to a second container, is well recognized in the prior art. One problem with such pipette is that in order to measure and transfer a given quantity of liquid, a great deal of care must be exercised in order to insure accuracy. While prior art methods are satisfactory, in terms of accuracy, they are very time consuming. Recent advances in the microbiological, immunological and other medical laboratory research have made such approach outmoded. This is because such system may require the container with the liquid to be measured and transferred to be open to the atmosphere each time the pipette is filled. In many procedures, continued and repeated exposure to the atmosphere can lead to poor results. Further, today mass sampling and testing is typically done. If individual samples had to be taken, even if there were no adverse consequences, the time factor using old methodologies and systems would slow research to a snail's pace.
The prior art has recognized these problems and has come up with a number of different systems which are alleged solutions. These devices are adapted to be used with multi-well trays, with a liquid sample in each well or in a tube disposed in each well. More recent devices are adapted to simultaneously withdraw a relatively large number of samples from the individual tubes or wells which contain the sample. Devices of such type are shown in U.S. Pat. Nos. 3,982,438; 4,158,053; 3,261,208; and 3,568,735. A review of these patents, however, will illustrate that while a solution is provided to the transfer of fluid from multi-well laboratory trays such are now extensively used in microbiological and immunological laboratory work, they are relatively complex and expensive.
One solution to the problem associated with these prior art devices is shown in my co-pending application Ser. No. 307,745, which is herein incorporated by reference. The pipette sampler system of the present invention represents yet a further improvement over the prior art and the previous application, in that it provides a method for sampling without the complexity or expense associated with prior art devices, but enables the system to be adapted such that various sized samples may be taken.